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GlassWalker

PST eyepiece area disassembly

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Note I have two PSTs now. One was bought new from earlier this year, serial 1076xx. The older one I bought used, the previous owner said it was about 4 years old. Serial number 1042xx. Both are blue objective style ones.

eph.jpg

The shaved eyepiece holder. Since the body was scratched I decided to sand it which gives it a brushed metal finish. The blocking filter to the right fell out while I was doing that. It pops in from the top and is held in by a ledge so it doesn't fall out. And to stop it going up, it was glued. Push from the bottom and it should come out.

Originally I was going to remove 4mm, but now I hold it next to the unmodified one, I've taken off 5mm or more once the filing and sanding is taken into consideration.

eyepieces.jpg

Top row left to right: Unmodified eyepiece section, shaved eyepiece section with blocking filter removed, lower section with ERF removed.

Lower row left to right: unmodified lower section with ERF, blocking filter without holder, ERF without lower section.

bfu1.jpg

The ERF from the old scope, viewed from the lower side (nearest prism). Showing significant signs of damage. To remove this from the lower section, put something into the holes for grip then twist.

bfu2.jpg

The same ERF, but from a slightly different angle.

bft1.jpg

The same ERF, but from the top side.

bft2.jpg

ERF from the new PST, top side. Looks totally different.

bfd.jpg

The ERF from the old PST, disassembled further. The clip on the top holds it in once you remove the black gunk. The ERF is a sandwich of three layers.

As a general comment, the ERF seems different between the two models even putting aside the damage on the old one. The new one is a golden colour reflection viewed from either side. The old one is golden on the prism side surface only, and red on the top.

I noticed the blocking filter section can be dropped into the top of the lower section. When the eyepiece section is screwed back in it holds it tightly. So if it isn't too far down to cause image issues that could be an alternative to gluing it back into the top section.

If anyone finds these images useful and wants to use them elsewhere, feel free to do so.

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